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121.
目的对研制的二乙酰吗啡盐酸盐标准物质进行定值,并评定定值结果的不确定度。方法采用定量核磁共振法和质量平衡法进行定值;采用液质联用法用于有机物杂质的定性分析,采用电感耦合等离子质谱法、离子色谱法、顶空-气质联用法和卡尔费休滴定法测定无机阳离子、阴离子、挥发性有机溶剂残留和水分等杂质的含量。结果定量核磁共振法的纯度为95.6%,不确定度为0.13%;质量平衡法的纯度为95.3%,不确定度为0.93%。结论二乙酰吗啡盐酸盐标准物质的纯度值为95.6%,扩展不确定度为1.2%(k=2)。  相似文献   
122.
考核模式改革是我校"教学重心转变"工作中教学模式改革的重点和核心内容之一。本文通过对《特殊痕迹检验》课程考核模式的改革与实践,提出了适应本专业学生教学练战一体化的考核模式。  相似文献   
123.
Abstract:  With improvements in manufacturing procedures, comparing physical characteristics of paper samples may not offer sufficient discrimination among different vendors. In this work, the potential to differentiate paper samples based on trace element concentrations was investigated. Paper samples from two different vendors were microwave-digested and trace element concentrations (Mg, Al, Mn, Fe, Sr, Y, Ba, Ce, and Nd) were determined using inductively coupled plasma–mass spectrometry. Differences in concentration were assessed statistically using two-way ANOVA and Tukey's honestly significant differences test. Elemental concentrations were shown to be consistent across a single sheet as well as within a single ream of paper for each vendor. Reams from vendor A were differentiated based on Al and Ba concentration while reams from vendor B were differentiated based on Mg, Mn, and Sr concentrations. Paper was differentiated according to vendor based on significant differences in Ba, Sr, Ce, and Nd concentrations.  相似文献   
124.
Abstract: High‐energy synchrotron radiation x‐ray fluorescence spectrometry (SR‐XRF) utilizing 116 keV x‐rays was used to characterize titanium dioxide pigments (rutile) and automotive white paint fragments for forensic examination. The technique allowed analysis of K lines of 9 trace elements in 18 titanium dioxide pigments (rutile), and 10 trace elements in finish coat layers of seven automotive white paint fragments. High‐field strength elements (HFSE) were found to strongly reflect the origin of the titanium dioxide (TiO2) pigments, and could be used as effective parameters for discrimination and classification of the pigments and paint fragments. A pairwise comparison of the finish coat layers of seven automotive white paint fragments was performed. The trace elements in the finish coat layers detected by the high‐energy SR‐XRF were especially effective for identification. By introducing the trace element information of primer and electrocoat layers, all the automotive white paint fragments could be discriminated by this technique.  相似文献   
125.
Abstract:  A young male was shot to death by a police officer with a Chinese Type 64 7.62 mm pistol when he was dealing with an aggravated assault arising from a traffic accident. By using scanning electron microscopy and energy dispersive X-ray spectroscopy (SEM/EDX), trace deposits on the discharged bullet and the intermediate target, i.e., a concrete telegraph pole at the scene, were identified to be from each other. The result demonstrated the bullet causing the death ricocheted from the concrete telegraph pole before striking the victim, thus indicating the incident was accidental. The case report illustrates the evidential value of trace materials derived, respectively, from discharged bullets and intermediate targets in bullet–intermediate target interaction for trajectory reconstruction. In addition, it indicates that the SEM/EDX method with its nondestructive nature, compared to other methods, may be more helpful in certain situations in determining the origins of trace evidentially valuable deposits on substrates.  相似文献   
126.
航空国际私法领域中弱者利益保护问题初探   总被引:1,自引:0,他引:1  
21世纪国际航空运输已成为各国人员和货物流动的主要方式,一旦发生航空事故常常伴随着机毁人亡的灾难性后果。作为消费者的旅客和托运人这一弱势群体利益的保护和救济便成为人们关注的焦点和司法实践的主要问题之一。本文主要对航空私法领域中弱者利益保护的必要性、保护的方法和公约的立法方面作初步探讨。  相似文献   
127.
128.
The 608-bp hypervariable region 1 (HV1) sequences from 36 local dogs were analyzed to characterize the population genetic structure of canid mitochondrial DNA (mtDNA). Sixteen haplotypes were identified. A 417-bp segment of this sequence was compared with GenBank sequences from a geographically representative sample of 201 dogs, two coyotes, and two wolves. Sixty-six haplotypes were identified including 62 found only in domestic dogs. Fourteen of these correspond to the 16 local haplotypes and were among the most frequent haplotypes. The local sample was judged to be representative of the much broader geographic sample. No correlation was observed between local haplotypes and the owner's characterization of dog breed. A 60-bp variation "hotspot" within the canid HV1 was identified as a potentially valuable molecular tool, particularly for assaying limited or degraded DNA samples.  相似文献   
129.
进入21世纪以来,随着现代信息网络技术的迅猛发展,互联网络开始走入并深深地影响着人们的生活,同时,虚拟财产也进入人们的视野。由于人们对虚拟财产的法律属性认识不一,产生了大量法律纠纷,影响了社会秩序,损害了当事人的权益。剖析虚拟财产的属性,选择适当立法模式,为虚拟财产提供及时有效的法律保护,有着较强的实践意义。  相似文献   
130.
萨米人是北欧的土著民族,也是跨界民族。俄罗斯的萨米人主要分布在科拉半岛,他们在这里创造了独特的物质文化和精神文化。他们的文化高度适应极北严酷的自然条件,反映了人与自然的统一。  相似文献   
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